Safety inner tube



May 20, 1941. A. MARKS SAFETY INNER TUBE Filed Nov. 14, 1939 141125501Mir/( V VEN TOR.

A TTORNEYS.

i atented May 20, [941 2,242,788 SAFETY INNER ITUBE, Anthony Marks,Youngstown, Ohio Application November 14, 1939, Serial No. $414,339

2 Claims.

This invention relates to a safety inner tube.

The principal object of this invention is the provision of an inner tubeadapted to support a pneumatic tire while both inflated and deflated andparticularly at such times as the tire casing itself is ruptured orblown out.

A further object of the invention is the provision of an inner tubecomprising dual air chambers adapted to be inflated through individualmeans and which air chambers normally support the weight of the vehicleupon the tire within which the inner tube is positioned.

A further object of the invention is the provision of an inner tubecomprising dual air chambers positioned above and below a cushioningsection of suitable resilient material.

Specifically, the safety inner tube shown and described herein has beendesigned so as to provide an inner tube which in normal inflatedcondition possesses exactly the same characteristics ;as theconventional inner tubes now commonly in use but which actually takesthe form of a yieldable cushion suspended between an outer .and innerinflatable section.

With the foregoing and other objects in View which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts and. in the details of construction hereinafterdescribed and claimed, it being understood that changes in the preciseem- ;bodiment of the invention herein disclosed, can be made within thescope of what is claimed without departing from the spirit of theinvention.

The invention is illustrated in the accompanying drawing, wherein:

Figure 1 is a cross sectional elevation of a tire casing showing a crosssectional View of the safety inner tube positioned therein.

Figure 2 is a cross sectional side elevation of a section of the safetyinner tube shown in Figure 1.

It is well known that many and various attempts of providing a blowoutproof inner tube have been made, the most successful heretofore of whichhave comprised the tube within a tube structure commonly referred to asa blowout proof inner tube. One of the objections to this type of tubeis the loosening of the innermost tube from its annular connection withthe inner tube itself which frequently results in the rupture of thecomplete tube thus rendering it useless. Another objection is in thedifficulty of inflating the tube within a tube structure to properpressure as the equalizing opening in the innermost tube is of suchsmall size that quite commonly the tube is only partially inflated atthe time of inflation due to the inability of a sufficient quantity ofair reaching the interior of the innermost tube through the smallopening. Another objection to this type of tube is that when the tubeitself is ruptured as in the case of a blowout the weight of the vehicleupon which it is positioned is carried for a short time upon theinnermost tube which rapidly deflates through the opening providedtherein. In order to overcome these objections the safety inner tubeshown and described herein has been designed and comprises an annulartubular structure I0 which has positioned midway therein an annularcushion ll of resilient material or light weight sponge rubber possessedof sufl'icient body to adequately support the weight of the vehicleuponwhich it is to be used. This annular cushion II is shaped so that anouter inflatable section I2 is provided which, of course, completelyencircles the annular cushion H and supports the tread portion E3 of atire casing M as it is positioned between this tread section I3 and theannular cushion H, Positioned around the innermost portion of thetubular structure It] there is a secondary inflatable section l5 whichgives the safety inner tube flexibility and enables its accurate andpositive positioning in the tire casing l4 upon a drop center wheel It.

By referring to Figure 2 of the drawing it will .be seen that the outerand inner inflatable sections l2 and I5 are provided with individualvalved inflation tubes I1 and l8 respectively which are preferablyformed of flexible material it being obvious that in order to bepractical the innermost portion [1A of the inflation tube I! is formedof yieldable material preferably a rubber tube so that when the completetube is inflated or deflated the changes in the relative positions ofthe various portions thereof will not affect the utility of theinflation tube ii. The inflation tubes I1 and iii are positionedadjacent each other so that they may conveniently pass through thesingle opening provided in most wheel structures and are formed offlexible material so that they may be separated sufficiently to permitthe application of inflation fitting to their respective valved ends. Itwill also be seen by referring to Figures 1 and 2 that the plurality offinger like depressions l9 may be formed in the annular cushion It inorder to reduce the weight thereof and to provide an additionalcushioning effect. It is obvious that these finger like depressions maybe formed entirely separate from the inflatable sections l2 and IE orthat they may communicate with either section as desired.

What I claim is:

1. An inflatable container adapted to be inserted in and removed from atire casing as a unit comprising a flexible annular cushion arrangedwithin a flexible annular tube of greater cross section, said cushionbeing joined to the said tube along its sides throughout itsentireperiphery so as to form inflatable sections above and below thesaid cushion, the said inflatable sections formed by the said flexibleannular tube, together with means for inflating each of the saidinflatable sections separately.

serted in and removed from a tire casing as a unit comprising a flexibleannular tube of relatively thin material having arranged therein anannular cushion member of relatively thick material, the said cushionmember being joined along its respective sides to the said flexibleannular tube so as to be spaced midway between a the inner and outerperipheries thereof so as to 2. An inflatable container adapted to bein-V 15 form separate and distinct inflatable annular chambers oneadjacent the outermost periphery of the flexible tube and one adjacentthe innermost periphery thereof, together with separate means forinflating the said sections.

ANTHONY MARKS.

